Inbeom lost his chance to befriend and/or date Seungtaek (he met Seungtaek first before Kyubin) but he chose to hurt him because of his insecurities & homophobia. Inbeom's case shows what happens when someone makes the wrong decisions.
Kyubin never hurt anyone (except Seungtaek & that was an agreement). The kid lost all his family (mother, father, sister, & grandmother) but he never went around terrorizing anyone.
Seungtaek was terrorized by Inbeom practically from day one. Even when he told Inbeom to beat him up until he was satisfied (ch25), Inbeom still insisted on attacking him not only verbally but also physically using violence and/or touching inappropriately.
Seungtaek is owning up to his mistakes on ch111 & ch112.
4 out of the 5 kids in this story have accepted their sexual orientation and are currently in a loving relationship. Inbeom is the only one who needs to let go of his fears and accept that there is nothing wrong with liking a boy. If he doesn't, he might hurt someone in the future again.
Inbeom seemed like he could have been a nice person and a good friend but his past actions were not okay.
He deserves what he’s getting but man, is this seriously gonna be the second time he heads to the hospital? I thought i’d see move character development for kyubin, seungtaek and inbeom. They all really need to get their shit straight.